This invention relates generally to apparatus for processing container closures and caps prior to use thereof; and, more specifically relates to apparatus for inserting liners into such closures, and for inspecting same for suitability for an intended application.
Container closures and caps manufactured, for example, of plastics or the like by such techniques as molding, are utilized with myriad products in consumer, industrial, and other applications. In the majority of present applications for these closures, they are commonly provided with an insert or liner prior to use thereof. The liner, which may comprise a slightly compressible plastic or similar material, is affixed within the cap interior, as by being adhered thereto by an adhesive composition. The liner serves an important function in assuring a proper seal with the container with which the closure is utilized.
In the past, the aforementioned liners have been inserted into the molded or other caps, by use of various apparatus. Thus in a typical prior art device a rotatable indexing table is utilized, which table is provided with a plurality of stations. Thus, at a first station the caps may be properly oriented; at a second station an adhesive material may be dispensed to the cap interior; at a third station, the liners may be emplaced and tamped, or so forth.
While apparatus of the foregoing type have, in a number of instances, been reasonably well adapted to the mentioned lining function, an ever-increasing interest has been generated in the objective of inspecting the aforementioned caps, in order to determine their true suitability for the ultimate use thereof. It may be noted in this connection that a number of serious problems are commonly encountered in closures of the aforementioned type, both in consequence of the defects in the closure shell proper, i.e. irrespective of the liner; and in the product which results from the lining operation. The shell may, for example, be the result of a "short shot" in the molding process, i.e. an insufficient quantity of plastic is provided during the molding process, resulting in voids or incompleted portions of the shell. Similarly, the liner itself can be improperly emplaced as, for example, by being cocked at an angle; or the liner may simply not be adhered in proper fashion. All of these defects, and others, can result in an ultimate product which is incapable of maintaining a proper closure for the container with which it is utilized; and such fact can, in turn, result in leakage from the container. Depending upon the nature of the contents of such container, the result can be not merely inconvenience, but possibly danger to the consumer or other individuals concerned with the container contents. Leakage can also have dire economic consequences for the manufacturer or distributor, who may be forced to discard large shipments because of damage from a limited number of leaking containers.
Finally, it may be observed that in a recent type of closure that has come into use in the container industry, liners have been eliminated by molding into the closure an internal lip, which engages with the top of the container with which the closure is utilized. Such lip effectively functions in the manner of a liner, i.e. to seal with the said container. Even in these instances, however, the various closure shell imperfections and defects that have already been alluded to, can once again be present, i. e. said closures can be the results of a short shot during the molding process, or they may, for other reasons, be cracked, damaged or so forth. Once again, in these instances, the consequences of using such closures with a container can be an inconvenience or a relative disaster -- depending upon the specific application.
In accordance with the foregoing, it may be regarded as an object of the present invention, to provide apparatus which is adapted to insert liners into molded or other formed closures or caps, which apparatus is adapted, further, to inspect the said closures, both prior and subsequent to the lining operation, in order to determine the presence of defects which would prevent proper useage of the closures.
It is a further object of the present invention to provide lining and inspection apparatus of the aforementioned type, which is capable of processing large numbers of closures in rapid and virtually continuous fashion, and which rejects closures found to be defective without any requirement for shutting down the said apparatus and thereby generating lost production time.
It is a yet further object of the present invention, to provide apparatus of the foregoing type, which includes means for directly punching and emplacing cap liners from a continuous web provided to the machine; and which further, includes provision for adjusting the web feed so as to insure high utilization for the web material.
It is a still further object of the present invention, to provide apparatus of the foregoing type, which includes simple and highly effective means for adjusting the apparatus to handle a variety of closure sizes with equal facility.
It is a still additional object of the present invention, to provide apparatus which is capable of inspecting closures and caps of the linerless type, in order to determine the presence therein of defects which would impair the usefulness of same for use in container applications.